Air conditioning system



9, 1938. F. B. FILLO 2,126,182

AIR CONDITIONING SYSTEM Filed Sept. 5, 1935 2 Sheets-Sheet 1 B.Z z'ZZ 0M- KM Aug. 9, 1938. 3 o 2,126,182

' A R CONDITIONING SYSTEM Filed Sept. 5, 1935 2 Sheets-Sheet 2yPatenteci Aug. 9, 1938 UNITED STATES PATENT OFFlCE AIR CONDITIONINGSYSTEM Application September 2 Claims.

This invention relates to air conditioning sys tems.

An object of this invention is to provide an air conditioning system formaintaining the rela 5 tive humidity of a space constant and formaintaining the temperature of a space constant when used for eithersummer cooling or winter heating.

Another object of this invention is to provide an air conditioningsystem wherein an air conditioning unit, having humidifying means andtemperature changing means, conditions the air delivered to a space, andwherein the space provided with humidity responsive means andtemperature responsive means for controlling the humidiiying means andthe temperature changing means to maintain the temperature and relativehumidity of the space constant.

More specifically, it is an object of this invention to provide an airconditioning system of the type described wherein the thermostatic meansoperates the temperature changing means to supply heat to the space whenthe space temperature decreases, and to abstract heat when the spacetemperature increases, and wherein the humidity responsive deviceoperates the humidifying means when the space relative humiditydecreases and operates the temperature changing means when the relativehumidity increases.

Still another object of this invention is to provide an air conditioningsystem of the class de scribed, wherein the space thermostat operates aheating means when the space temperature decreases and operates acooling means when the space temperature increases, and wherein thespace humidostat operates a humidifying means when the relative humiditydecreases and operates the cooling means when the relative humidityincreases.

Still another object of this invention is to provide an air conditioningsystem of the class described, wherein the space thermostat operates aheating means when the space temperature decreases and operates acooling means when the space temperature increases, and wherein thespace humidostat operates a humidifying means when the relative humiditydecreases and operates a heating means when the space relative humidityincreases.

A further object of this invention is to provide a de-humidifying meansfor a space comprising cooling means, heating means, a humfdostatresponsive to increases in relative h .idity to cause operation of thecooling means cool the air delivered to the space and thereb condenseout the water vapor in that air, and a 5, 1935, Serial No. 39,277!

(Cl, Kid-4d) thermostat responsive to a'decreased space temperaturecaused by the admission of the cooled air for operating the heatingmeans to re-heat the cooled air, whereby heated dry air is admitted tothe space to decrease the relative humidity in the space.

Still another object of this invention is to provide a de-humidifyingmeans for a space comprising cooling means and heating means, ahumidostat for placing the heating means in operation when the spacerelative humidity is high deliver heated air to the space, and aresponsive to an increase in space tempe- 2. e caused by the delivery orthis heated air to place the cooling means in operation, whereby the airis cooled and the water vapor therein condensed out to deliver heateddry air to the space to reduce the relative humidity therein.

Other objects and advantages will become apparent to those skilled inthe art upon reference to the accompanying specification, claims anddrawings, in which drawings:

Figure 1 is a diagrammatic showing of one form of my invention; and

Figure 2 is a diagrammatic showing of another form of my invention.

My air conditioning system is shown as applied to a space or room ii,the air of which is to he conditioned. Conditioned air is supplied tothe room or space iii through a grill i by a conduit or duct ii. A fanIt forces the conditioned air into the duct or conduit I! from an airconditioning unit generally designated at it. The air conditioning unitIt is shown to comprise an air cleaner or purifier E5, of usual design,a humidifying spray i6, a set of cooling coils ii, and heat ing elementswhich may take the form of electric heating coils 58. Located at thebottom of the conductor H is a drain pan to collect the excess of waterdelivered by the humidifying spray it and to allow drainage of the samefrom the conditioning unit It through a pipe 2?.

The fan i3 is driven by an electric motor 25 through any suitable meanssuch as'a belt 22. The motor H is connected by a wire 8 and by a wire 9,a switch 23 and a wire 24 to line wires 25 and 26 leading from somesource of power, not shown. The switch 23 may be manually operated andwhen closed a circuit is completed from the line wire 26, through wire2%, switch 23, wire 9, electric motor 2| and wire 8 back to the otherline wire 26 to cause operation of the motor 29 and the fan l3 todeliver air from the conditioning unit is into the space or room In, tobe conditioned.

Water is supplied for humidifying purposes to the humidifying spray l6through a pipe 21 emanating from some source of water, not shown. Avalve 28 is located in the pipe 21 to control the flow of water to thehumidifying spray l6, the valve 28 being in turn controlled by asolenoid 29. The arrangement is such that when the solenoid 29 isenergized the valve 28 is opened to cause operation of the humidifyingspray l6, and when the solenoid 29 is de-energized the valve 28 isclosed to prevent the further operation of the spray |6.

Cooling coil l1 may form a portion of a mechanical refrigeratingmechanism which may comprise an expansion valve 38, a condenser 3| and acompressor 32, all of which is well known in the art. The compressor 32may be operated by an electric motor 34 through any connecting meanssuch as a belt 33. Upon energization of the electric motor 34 thecompressor 32 is placed in operation to cause cooling of the coolingcoil H to cool the air passing through the air conditioning unit l4.Upon de-energization of the electric motor 34 further cooling of the airin the air conditioning unit I4 is prevented.

Located in the room or space |8 to be conditioned is a thermostatgenerally designated at 35. The thermostat may comprise a bimetallicelement 36 which carries contacts 31 and 38 adapted to engage spacedcontacts 39 and 48. The bimetallic element 36 also carries contacts 4|and 42 which are adapted to engage spaced contacts 43 and 44,respectively. The distance between contacts 31 and 39, and 38 and 48, isless than the distance between contacts 4| and 43; and 42 and 44.Therefore, upon an increase in temperature aflecting the bimetallicelement 36, the contact 31 is first moved in the direction designated bythe character H into engagement with contact 39, and then upon a furtherslight increase in temperature the contact 4| is moved into engagementwith the contact 43. Likewise, upon a decrease in temperature thecontact 38 is moved in the direction of the character C into engagementwith the contact 48 and upon a further slight decrease in temperaturethe contact 42 is moved into engagement with the contact 44.

Also located in the space or room ID to be conditioned is a humidityresponsive switching mechanism 45 termed herein as a humidostat. Thehumidostat 45 comprises a lever 46 pivoted at 41 and carrying a switcharm 48, which is adapted to engage spaced contacts 49 and 58. The lever46 is urged in a counter-clockwise direction by an adjustable tensionspring Connected to the lever 46 is a humidity responsive element 52which may take the form of hair, which in turn is secured to anadjustable lever 53 pivoted at 54. Upon a decrease in relative humiditythe humidity responsive element 52 contracts and acts against thetension of the spring 5| to move the switch arm 48 in the directionindicated by the character D into engagement with the contact 49. Uponan increase in relative humidity the humidity responsive element 52expands to allow the spring 5| to move the switch arm 48 in thedirection indicated by the character W into engagement with the contact58. By reason of the adjustable tension spring 5|, and the adjustablelever 53, the values of the relative humidity which will cause movementof the switch arm 48 into engagement with the contacts 49 and 58 may beiusted.

Connected across the line wires 25 and 26 is a primary 55 of a step-downtransformer 56, having asecondary 51. One end of the secondary 51 isconnected by wires 58, 59 and 68 to the solenoid 29 of the valve 28, andthe solenoid 29 is in turn connected by a wire 6i to the contact 49 ofthe humidostat 45. The switch arm 48 is connected by wires 62, 63 and-64to the other end of the secondary 51. Therefore, when the relativehumidity in the space or room l8 decreases to a predetermined value soas to move the switch arm 48 into engagement with the contact 49, acircuit is completed from the secondary 51, through wires 58, 59 and 68,solenoid 29, wire 6|, contact 49, switch arm 48, and wires 62, 63 and 64back to the secondary 51. Completion of this circuit causes energizationof the solenoid 29 to open the valve 28 to spray water into theconditioning unit I4 to restore the relative humidity of the space |8 tothe normal value. When the relative humidity of the space i8 has beenrestored to the normal value the switch arm 48 is moved out ofengagement with the contact 49 to cause de-energization of the solenoid29 and prevent the further supply of moisture'to the air passing throughthe conditioning unit |4.

The other contact 58 of the humidostat 45 is connected by wires 65, 66and 61 to one end of a relay coil 68 and the other end of the relay coil68 is connected by a wire 69 to the junction of wires 58 and 59.Therefore, when the relative humidity of the space or room l8 increasesabove a predetermined value so as to move the switch arm 48 intoengagement with the contact 58, a circuit is completed from thesecondary 51, through wires 64, 63 and 62, switch arm 48, contact 58,wires 65, 66 and 61, relay coil 68, and wires 69, and 58 back to thesecondary 51. This causes energization of the relay coil 68 to moveswitch arms 18 and 1| into engagement with contacts 12 and 13. When therelative humidity of the space I8 decreases to a normal value, theswitch arm 48 moves out of engagement with the contact 58 to break thecircuit through the relay coil 69 to cause de-energization of the sameto causemovement of the switch arms 18 and 1| out of engagement with thecontacts 12 and 13. This movement of the switch arms 18 and 1| may becaused by springs, gravity or other means, not shown.

The contact 39 of the thermostat 35 is connected by a wire 14 to thejunction of wires 62 and 63 and the contact 43 is connected by a wire 15to the junction of wires 65 and 66. The bimetallic element 36 of thethermostat 35 is connected by wires 16 and 11 to the contact 12 and theswitch arm 18 associated with the contact 12 is connected by a wire 18to the Junction of wires 66 and 61. When the room temperature increasesabove a predetermined value the contact 31 is moved into engagement withthe contact 39 and upon a further slight increase in space temperaturethe contact 4| is moved into engagement with the contact 43. This causescompletion of a circuit from the secondary 51 through wires 64, 63 and14, contacts 39, 31, 4| and 43, wires 15, 66

and 61, relay coil 68 and wires 69 and 58 back to the secondary 51. Thiscauses energization of the relay coil 68 to move the switch arms 18 and1| into engagement with the contacts 12 and 13. Movement of the switcharm 18 into engagement with the contact 12 completes a maintainingcircuit from the secondary 51 through wires 64, 63 and 14, contacts 39and 31, bimetallic element 88, wires 15 and 11, contact 12, switch arm18, wires 18 and 51, relay coil 88 and wires '88 and 58 back to thesecondary 51. This maintaining circuit maintains the relay coil 58energized until the space temperature drops sufflciently far to breakcontact between the contacts 81 and 88, at which time the switch arms 18and 1| are moved out of engagement with the contacts 12 and 18.

This invention also contemplates the use of a relay coil 18 foroperating switch arms 88 and 8|. When the relay coil 18 is energized theswitch arms 88 and 8| are moved into engagement with contacts 82 and 88,and when the relay coil 18 is de-energized the switch arms 88 and 8| aremoved out of engagement with their respective contacts by means ofsprings, gravity or other means, not shown. One end of the secondary 51is connected by the wire 84 and a wire 84 to the contact 48 of the spacethermostat 85. The other contact 44 is connected by wires 85 and 85 toone end of the relay coil 1.8. The other end of the relay coil 18 isconnected by wires 81, 58 and 58 to the other end of the secondary 51.The contact 82 is connected by a wire 88 and the wire 18 to thebimetallic element 88 and the switch arm 88 associated with the-contact82 is connected by a wire 88 to the junction of wires 85 and 88.

Upon a decrease in space temperature below a predetermined value thecontact 88 is moved into engagement with the contact 48 and upon afurther slight decrease in space temperature the contact 42 is movedinto engagement with the contact 44. This causes completion of a circuitfrom the secondary 51 through wires 54 and 84, contacts 48, 88, 42 and44, wires 85 and 85, relay coil 18 and wires 81, 58 and 58, back to thesecondary 51. Completion of this circuit causes energization oi! therelay coil 18 to move the switch arms 88 and 8| into engagement with thecontacts 82 and 88. Movement of the switch arm 88 into engagement withthe contact 82 completes a maintaining circuit from the secondary 51through wires 54 and 84, contacts 48 and 88, bimetallic element 88,wires 15 and 88, contact 82, switch arm 88, wires 88 and 85, relay coil18, and wires 81, 58 and 58, back to the secondary 51. Completion ofthis circuit maintains the relay coil 18 energized until the spacetemperature increases to a value which is suflicient to break contactbetween the contacts 88 and 48, at which time the relay coil 18 istie-energized to move the switch arms 88 and 8| out of engagement withcontacts 82 and 88.

The contact 18 is connected by a wire88 to the line wire 25, and theswitch arm 1| associated with the contact 18 is connected by a wire 8|to the electric motor 84 operating the compressor 82. The motor 84 is inturn connected by a wire 82 to the line wire 25. Therefore, when therelay coil 58 is energized in the manner pointed out above, a circuit iscompleted from the line wire 28, through the wire 88, contact 18, switcharm 1|, wire 8|, electric motor 84 and wire 82, back to the other linewire 25, to cause operation of the compressor 82 of the mechanical refrigerating mechanism to abstract heat from the air passing through theair conditioning unit H.

The contact 88 is connected by a wire 88 to the line wire 28.- Theswitch arm 8|, associated with -the contact 88 is connected by a wire 84to the electric heating elements l8. The electric heating elements l8are in turn connected by -a wire 85 to the other line wire 25.Therefore, when the relay coil 18 is energized in the manner pointed outabove, a circuit is completed from the line wire 25 through wire 88,contact 88, switch arm 8|, wire 84, electric heating elements l8 andwire '85, back to the other line wire 25, to cause energization of theheating elements |8 to impart heat to the air passing through the airconditioning unit i4.

With the parts in the position shown in Figure l the relative humidityof the space i8 is normal and the temperature within the space i8 isnormal. Therefore, the switch arms of the humidostat ,45 and thethermostat 85 are in a mid position and the relay coils 58 and I8 arede-energized whereby the humidifying spray I6 is inoperative, themechanical refrigerating mechanism is inoperative and the electricheating elements are inoperative. Upon a decrease in room or spacetemperature the relay coil 18 is energized to cause operation of theelectric heating elements l8 to impart heat to the air being deliveredto the space l8 to restore the temperature within the space i8 tonormal. When the temperature has thus been restored to normal, the relaycoil 18 is de-energized to move the switch arms 88 and 8| away from thecontacts 82 and 88 to prevent the further supply of heat to the airbeing delivered to the space l8. When the temperature of the space i8increases above a given value the relay coil 68 is energized to causeoperation of the mechanical refrigerating mechanism to abstract heatfrom the air delivered to the space |8 to cool the same. When thetemperature of the space l8 decreases to the normal value relay coil 88is de-ehergized moving arms 18 and 1| to open contacts 12 and 18 to stopoperation of the mechanical refrigerating mechanism to prevent thefurther delivery of cold air to the space l8. When the relative humidityof the space i8 decreases below a predetermined value, solenoid 28 isenergized to operate the humidifying spray i to impart moisture to theair being delivered to the space l8, and when the relative humidity ofthe space l8 increases back to normal the solenoid 28 is de-energized toprevent further imparting of moisture to the air being delivered to thespace or room. When the relative humidity in the space |8 increasesabove a predetermined value the relay coil 68 is energized to causeoperation of the mechanical refrigerating mechanism. This causes coolingof the air passing through the air conditioning unit i4 to condense outmoisture or water vapor in the air passing through the air conditioningunit i4. This cooled air carrying less water vapor is delivered to thespace l8 and when the space temperature decreases to a predeterminedvalue the relay coil 18 is energized to cause operation of the heatingcoils l8 to re-heat the air after it has been cooled by the cooling coilH. In this manner when the relative humidity of the space or room i8 istoo high the air delivered to the room is cooled to abstract moisture orwater vapor therefrom and the air is then supplied with heat by theheating coils i8 to maintain the space temperature at the desired value.When the relative humidity in the space I8 is restored to the normalvalue in this manner, the relay coil 58 is de-energized to preventfurther operation of the mechanical refrigerating mechanism to preventthe further abstracting of moisture from the air passing through the airconditioning unit l4, and when the space temperature again becomesnormal relay coil 18 is de-energized to prevent the further imparting ofheat to the air passing through the air conditioning unit l4.

From the above it is seen that I have provided an air conditioningsystem wherein the temperature of a space is maintained at a desirednormal value and wherein the relative humidity of the space is alsomaintained at a desired normal value, which system may be used foreither summer cooling or winter heating.

Referring now to Figure 2, like elements and connecting wires have beenused throughout, and like reference characters referring to theseelements and connections have been applied in Figure 2. Figure 2 differsfrom Figure 1 in that the bimetallic element 36 of the space thermostat35 is reversed so that when the space temperature increases above apredetermined value the contacts 38 and 42 are sequentially moved intoengagement with the contacts 40 and 44 to cause energization of therelay coil 19, and when the space temperature decreases to apredetermined value the contacts 31 and 4| are moved sequentially intoengagement with the contacts 38 and 43 to cause operation of the relaycoil 68. Also, the wires ill and 92 controlled by the switch arm 1i leadto the electric heating elements IS in Figure 2 instead of to theelectric motor 34 of the mechanical refrigerating mechanism as inFigure 1. Likewise, the wires 94 and controlled by the switch arm 8|lead to the electric motor 34 of the mechanical refrigerating mechanisminstead of to the electric heating elements l8 as in Figure 1.

Therefore, in Figure 2 when the space temperature decreases below apredetermined value the relay coil 68 is energized to cause operation ofthe heating element I8 to restore the temperature of the space I!) tonormal. Likewise, when the space temperature increases above apredetermined value the relay coil 19 is energized to cause operation ofthe mechanical refrigerating mechanism to restore the temperature of thespace II) to normal. In Figure 2, as in Figure 1, a decrease in relativehumidity below a predetermined value causes energization of the solenoid29 to cause operation of the humidifying spray it to impart water vaporto the air passing through the air conditioning unit l4 to restore therelative humidity of the space in to normal. However, in Figure 2 anincrease in relative humidity causes operation of the heating elementsI8 instead of the mechanical refrigerating mechanism as in Figure 1.Operation of the heating elements l8 in this manner increases thetemperature of the space In to move the contacts 38 and 42 intoengagement with the contacts 40 and 44. This causes energization of therelay coil 19 to cause operation of the mechanical refrigeratingmechanism. Operation of the mechanical refrigerating mechanism in thismanner decreases the temperature of the air passing through the airconditioning unit i4 to condense out water vapor or moisture in the airand then this drier air is re-heated by the electric heating coils i8 todeliver warm dry air to the space H) to restore the relative humidity ofthe space Hi to normal. When the relative humidity of the space ID hasbeen so restored to normal the relay coil 68 is tie-energized to preventthe further application of heat to the air passing through the airconditioning unit l4 and when the temperature of the space i0 decreasesto a predetermined normal value the relay coil 19 is de-energized toprevent further operation of the mechanical refrigerating mechanism.

In both modifications of my invention I have provided means whereby thetemperature of a space or room may be maintained constant and wherebythe relative humidity of the space or room may also be maintainedconstant. In the showing set forth in Figure 1 an increase in relativehumidity in the space ill causes operation of the mechanicalrefrigerating mechanism directly to first decrease the temperature ofthe air being delivered to the space l0 and the air so delivered is thenre-heated under the command of the space thermostat. In Figure 2 anincrease in relative humidity in the space Iii causes operation of theheating coils ii! to increase the temperature of the air being deliveredto the space I 0 and then the mechanical refrigerating mechanism isplaced in operation under the control of the room thermostat to decreasethe temperature of the air being delivered to the space i 0. In bothinstances, however, an effective control has been provided to preventthe existence of a relative-humidity greater than a predetermined value.

Although I have disclosed two forms of my invention for purposes ofillustration, other forms thereof may become apparent to those skilledin the art, and, consequently, this invention is to be limited only bythe scope of the appended claims and the prior art.

I claim as my invention:

1. In a control system for a space air conditioning apparatus havinghurnidifying means, cooling means and heating means, the combination of,means responsive to space temperature, means connecting at all times thespace temperature responsive means with the heating means and thecooling means to cause heating when the space temperature decreases andcooling when the space temperature increases, means responsive to spacerelative humidity, and means connecting at all times the space relativehumidity responsive means with the humidifying means and the heatingmeans to cause humidifying when the space relative humidity decreasesand heating when the space relative humidity in-- creases.

2. In an electrical control system for a space air conditioningapparatus having electrically controlled humidifying means, coolingmeans and heating means, the combination of, electrical currentcontrolling means operated in response to variations in spacetemperature, electrical connections connecting at all times theelectrical current controlling means with the electrically controlledheating means and cooling means to cause heating when the spacetemperature decreases and cooling when the space temperature increases,electrical current controlling, means operated in response to variationsin space rela' tive humidity, and electrical connections connecting atall times the last mentioned electrical current controlling means withthe electrically controlled humidifying means and heating means to causehumidifying when the space relative humidity decreases and heating whenthe space relative humidity increases.

FRANCIS B. FILLO.

